yes, to answer your questions with Tomcat & Websphere, they all work fine, no problem.
I uploaded the jar file into the classpath of Sun ONE portal 6.0, using the same JSP that works with Tomcat & Websphere to test it out.
What I found so far is that the portal fell to handle any binary data. For example, if I got the following in a JSP Page, when I click submit, the portal returns a message "Portal encounter a serious error..etc..", and when I look at the /var/opt/SUNWam/debug/desktop.debug I saw an exception message saying failed to MultiParse etc.. (I haven't got it here in front of me), if this message is not clear, please let me know and I'll post the exact message.
Here is the form
<form action="dt" method="post" enctype="multipart/form-data">
<input type="file" name="fileToUpload">
<input type="submit" value="Go">
Note that the form hasn't got any logic in it, just to demonstrate the portal fails to receive incoming binary data. It parses OK when using text file. However, I still haven't got Oreilly working with Text file because when trying
ServletInputStream in = request.getInputStream() the portal throws error message as well.